Oxy-fuel gas powder laden cutting oxygen nozzle



April 18, 1950 E. M. HOLUB 2,504,526

OXY-FUEL GAS POWDER LADEN CUTTING OXYGEN NOZZLE Filed Sept. 3, 1947 'ny F.

INVENTOR EDWARD M. HOLUB BY ATTO Y Patented Apr. 18, 1950 OXY-FUEL GAS `POWDER `LADEN CUTTING OXYGEN NOZZLE Edward M. Holub, fElizabeth, N. J., assigner to The Linde Air Products Company, a corporation of l Ohio Application September 3, 1947, Serialo. 771,907

4 Claims. (Cl. `1141-422) This invention relates toblowpipe nozzles for thermo-chemically cutting, deseaming, or 'scarfing steel with a stream of oxygen 'and oxyifuel gas preheat names, and more particularly' to such nozzles which discharge `adiuvant powder containing iron, for example, in the cutting oxygen stream to assist the reaction in deseaming or scarfing diicult-to-cut metals such as stainless steel, cast iron andthe like.

The conventional Oxy-fuel gas nozzle which 1s adapted to, be usedv withoutpowder in the cutting oxygen stream, isprovided'with a cylindrical skirt surrounding the preheat oxy-fuel gas jets to prevent the flames from lblowing off the nozzle tip. Inthe past, operation of such conventional cylindrically-skirted type of oxy-iuelgas'nozzle proved to be quite impractical in powder cutting, scarfing and deseamingy due to objectional fusing and sintering of powder which collected in ythe skirt between the preheat flames.

Such accumulation of powder in the form of globules inside the skirt not only interfered with the Vpreheat gas flow, causing 'the names to be unstable and of insufcient temperature to Aburn the powder, but also actually distorted the cutting oxygen stream so that theV operation had to be discontinued while the 'built-up powder accumulation was removed from the skirt. Thus', muchtime was lost due to the necessity for stopping the deseaming or scarngoperatlon to vclean out the burned or sintered powderin the sliirt to restore the scarring efficiency of the nozzle. Previous attempts to 4solve the problem were entirely unsuccessful priorto ithe presentinvention.

The main object `of this invention is toelirninate such serious objection of the use of adjuvant powder in the cutting oxygen stream of Oxy-fuel blowpipe nozzles for cutting, sca'rng and deseaming operations'.

According to the invention, a novell Oxy-fuel o gas powder-laden cutting oxygen nozzle is yprovided in which an oxy-fuel gas jet expanding space is located between an inner,- tip surrounding the powder-laden cutting oxygen passageway and an outer skirt, in lateral communication with each of the oxy-fuel gas outlets, so that, in effect, the preheat jets pass between the internal tip and the external skirt, the internal tip protruding an appreciable distance or substantial amount beyond the external skirt to cause the powder in the cutting oxygen stream to burn completely outside of the nozzle. The result is that no portion of the powder builds up in a fused mass to obstruct the flow of the `preheat llame and cut- 2 ting gases,`as inthe case of conventional city-fuel gas nozzles.

Results with the nozzle of the present invention are excellent, not only with acetylene fuel but also with other fue1 gases, since 'the 'difficulties previously encountered with the conventional Oxy-fuel gas nozzle are eliminated. Heretofo're, no practical powder scarng nozzle was available which could use fuel gas other "than acetylene.

In the drawing:

Fig. 1 is a fragmentary view, mainly in longitudinal cross-section, of an Oxy-fuel 'gas powder scarng nozzle Villustrating the invention; ti Fig. 2 is an enlarged view 'in front end'el'eva- Fig. 3 is a similar view of the nozzle iii-rear end elevation; and

Fig. 4 is a fragmentary perspective View of the front end portion ofthe nozzle,`part ofthe outerv skirt being broken away to show the internal.

construction.

As shown in the drawing a nczzleN vis provided which includes an elongated body l0, composed of copper, having a central longitudinally extending powder-laden cutting-oxygen passage l2 and an annular series of longitudinally vextending Oxy-fuel gas passages I4 surrounding's'uch central passage l2. The rear end portion ofthe cutting oxygen passage l2 contains a Spud I6 composed of brass, having a central cutting oxygenpas'sage I8 and an annular flange "-20 provided with an annular series of adjuvant powder discharge grooves 22.

An annular recess in the s'pud f6 cooperates with the internal wall of the passage l2 inthe body I0 to provideyanV annular powder distributing space 24 communicating with the grooves 22, the nozzle body |20 hav-ing" an annularseries'of forwardly :and `inwardly inclined `powder inlet passages 26 leading to the space 2:4'.

The nozzle N is adapted toy `be connected to a powder deseaming blowpipe `-or desuracing`V head (not shown) in` a conventional manner', andi "is provided With a captivenut'l for' securing the nozzle to the blowpipefheadf. commerciallypure oxygen is delivered to the passage i8, a combustible mixture of oxygen and fuel gas, such as acetylene, butane, propane, city gas, etc.. is delivered to the inlet ends of the passages I4, and adjuvant powder composed mainly of iron, for example, is delivered to the powder inlets 26 with any suitable gas under pressure by the blowpipe or scarng head, not shown, to which the nozzle is attached, all in a manner well known to those skiued 1n the art.

The nozzle body I is also provided with an internal tip 30 as shown in the drawing, which surrounds the powder laden cutting oxygen ori- .ce 32 of the passage I2 and extends for a distance of the order of 0.030 inch beyond the front fend surface 34 of an annular outer sleeve or skirt 35, composed of copper. The passage I2 as well as the oxy-fuel gas preheat holes or passages I4 Vof the nozzle continue straight through the tip 30.

The front end portion of the body Ill is provided with an annular recess 36 which intersects the lateral walls of the outer end portions 3l of the passages I4, so that the front view of the body I0 presents a scalloped elect as illustrated in Figs. 2 and 4.

The outer skirt 35 which is relatively thick bears at its inner end against an annular shoulder and is silver soldered or bronze welded to the nozzle body I0 at 38. The inner wall of the skirt 35 cooperates with the recess 36 to form an annular space 39 which communicates with each of the end portions 3l of the Oxy-fuel gas passages I4, permitting expansion of the oxyfuel gasjets to insure lthe production of preheat flames which are stable and to prevent such llames from blowing off.

In operation, powder enters the nozzle N through the inlets 26 at the rear of the nozzle and is discharged through the passages 22 into the cutting oxygen passage I2 where it mingles with the cutting oxygen stream, the powderladen oxygen stream being discharged through the orice 32 in downstream relation with respect to the Oxy-fuel gas discharge ports at. As a result,A powder sintering on the inside of the skirt 35 is entirely eliminated, lyet hot stable preheat names are produced and, because of this, entirely satisfactory scarng speeds are obtained with the nozzle of the present invention.

I claim:

1. An Oxy-fuel gas powder-laden cutting-cxygen nozzle comprising a body having a powdere laden cutting-oxygen passage, said body also having a series of Oxy-fuel gas passages arranged about said powder-laden cutting-oxygen passage and an outer peripheral recess laterally intersecting the discharge end portions of said oxyfuel gas passages, an outer skirt mounted on the end portion of said body in spaced relation f to the lateral wall of said recess to provide a space in communication with the discharge end portions of such Oxy-fuel gas passages for expansion of the Oxy-fuel gas jets to insure the production of stable preheat names and to prevent the preheat flames from blowing off, the end surface of said outer skirt terminating a substantial amount upstream with respect to the front end surface of the body adjacent the discharge end of said powder-laden `cutting-oxygen passage, so that, in effect an inner tip is provided about the discharge end of such passage which protects the Oxy-fuel gas jet expansion space from objectionable powder accumulation.

2. An VOxy-fuel gas powder-laden oxygen- 4 scarng nozzle comprising a body having a ceritral longitudinally extending cutting oxygen passage and an annular series of longitudinally extending Oxy-fuel gas passages disposed around said central passage, passage means for feeding adjuvant powder composed mainly of iron into said cutting oxygen passage, an outer skirt mounted on said nozzle body, to provide an oxyfuel gas jet expansion space, the front end surface of said skirt being disposed an appreciable amount back of the front end portion of the nozzle body, so that the cutting oxygen laden with adjuvant powder is discharged downstream with respect to the oxy-fuel gas discharged from said Oxy-fuel gas jet expansion space, and hot stable Oxy-fuel gas preheating flames are produced with the elimination of sintered powder accumulations'on the inside of said skirt.

3.- A blowpipe nozzle comprising an elongated body having a central cutting oxygen passage and an annularly arranged series of oXy-fuel gas passages disposed around such central passage, said nozzle being provided with an inner tip at the outlet orifice of such central passage, which extends downstream` with respect to the outlet orifices of such Oxy-fuel gas passages, so that adjuvant powder discharged with the cutting oxygen streamis prevented from accumulating in the Oxy-fuel gas outlet orifices, and means providing an outer skirt surrounding and communieating laterally with such oxy-fuel gas outlet orifices to prevent the preheating flames produced by the Oxy-fuel gas jets from blowing oi, the front end surface of said outer skirt being located a substantial distance upstream with respect to the front end surface of said inner tip.

4. A blowpipe nozzle comprising the combination o f an elongated body composed of copper having a longitudinally extending passage for discharging a powder laden stream of cutting oxygen, said body also having at least one oxyfuel gas passage for discharging a preheating flame jet composed of a combustible mixture of oxygen and fuel gas, an outer skirt composed of copper mounted on the discharge end portion of said body to provide an expansion space for theoxy-fuel gas jet to prevent the preheating flame from blowing oli, and means providing an inner tip at the discharge mouth of said powder laden cutting oxygen stream passage which terminates an appreciable distance downstream with respect to said outer skirt and thereby entirely eliminates any undesirable accumulation of sintered powder in such jet expansion space adjacent the outlet of the Oxy-fuel gas passage.

EDSWARD M. HOLUB.

REFERENCES CITED .UNITED STATES PATENTS Name Date Stolle et al Apr. 11, 1916 Number 

